The White Mountain National Forest consists of nearly 800,000 acres of public land in northern New Hampshire and western Maine and it is managed for multiple land uses. Some 800 miles of roads and 1200 miles of trails bisect the mountains, rivers, and brooks of the National Forest to provide access for recreation, wildlife habitat management, and harvesting of forest products. Incorrectly sized or poorly located culverts can cause upstream depostion of stream substrate and woody debris potentially causing road failures due to the high stream power exhibited in White Mountain watersheds. These hydrologic changes caused by undersized culverts have the potential to limit the movement of Eastern brook trout into headwater streams. Potential stressors such as aluminum mobilization form acid depostion and increased water temperatures and reduced summer flows from climate change may be of greater concern where habitat fragmentation from culverts occurs. In order to reconnect stream hydrologic processes and aquatic species habitats, efforts are underway to improve stream crossings by implementing stream simulation design into crossing replacements. A Stream Crossing Inventory and Aquatic Organism Passage Assessment process has been designed to collect information to 1) map the landscape extent of stream crossings; 2) document the condition of stream crossings and their effect on stream hydrologic processes; 3) highlight those crossings which may put roads and stream habitats at risk; 4) assess the extent and location of aquatic organism barriers on the National Forest; and 5) document reference stream channel dimensions used to design stream simulation crossing replacements. A variety of stream simulation channel designs that have been implemented on stream channels less than 20' wide are presented.